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We’ve Only Just Begun...

Break out the thermostabilized beef tips with mushrooms and rehydratable apple cider! NASA is poised to celebrate a major space milestone on Nov. 2, as the international space station will clock its fifth anniversary of continuous human presence in space.

Since Expedition 1 arrived on the scene Nov. 2, 2000, the space station has grown and evolved into an unprecedented, state-of-the-art laboratory complex. Offering a microgravity environment that cannot be duplicated on Earth, space station continues to further humankind’s knowledge of science and how the human body functions for extended periods of time in space—all of which will prove to be vital on long-duration missions to Mars.

“It gives us unique access to the space environment, where we hope we can do very interesting and productive research, but it really means we [will] develop a lot of the capabilities and technology that'll allow humans to go elsewhere away from the planet,” Expedition 1 Commander Bill Shepherd said about the space station. “So, if we don't have this progress with this space station, it means that humans in space are pretty much destined to stay close to the Earth--and I don't think that's what humans are about.”

Solving Unsolved Mysteries

To date, 89 scientific investigations have been conducted on space station and more breakthroughs are to come. New results from early space station research, from basic science to exploration research, are being published each month.

For instance, there have been great strides made in understanding the significant rate of bone loss by crewmembers while in orbit, and where in the bones the loss is occurring. Also, a complete characterization study of the radiation environment in the space station has been done, with evaluation of models of radiation shielding by the station’s structure.

Everything from eating habits and nutritional deficiencies has been looked into to see how it all relates to the physiological effects of being in microgravity. New use of medical ultrasound equipment as a diagnostic tool and in-space soldering to repair potential hardware damage has also been tested on space station. And that’s only a tiny fraction of the studies conducted so far.

Expedition 9 Flight Engineer Mike Fincke, who had the opportunity to work with Advanced Diagnostic Ultrasound and In-Space Soldering while on space station, believes that many unknowns can be solved during expeditions.

“The International Space Station is a perfect stepping-stone for us to perfect the technology, to perfect the operational tempo, operational parameters that we need to in order to make those long-duration missions successful,” Fincke said.

A Silver Lining

Due to a space shuttle hiatus after the Columbia accident on Feb. 1, 2003, the space station had to become a more efficient research machine. Crews were limited to two people, and experiments and supplies had to be ferried to the orbiting outpost using either the Russian Soyuz or Progress ship.

However, what could have been a problem for the program turned into a unique learning tool. Future trips to Mars could take years to complete roundtrip, with little or no resupply opportunities, as well as limited cargo space. Repair techniques that are being perfected now could also be used during long-duration missions. Lessons taken from the space station during this period of heightened efficiency will help in planning for Mars missions later.

There’s No Place Like Home

As the space station has served as a science laboratory, it has also given crews something more important—a home away from home on Earth. During the upcoming five-year anniversary, the station will be home to its twelfth crew, Expedition 12. Inside the ultra-modern “home,” 15 Americans and 14 Russians have lived and worked aboard the space station.

This photo was taken of the space station shortly after space shuttle Discovery undocked during the STS-114 mission. Credit: NASA

With 15,000 cubic feet of habitable volume, more room than a conventional three-bedroom house, the space station affords many of the comforts one finds on Earth. There is a weightless “weight room” and even a musical keyboard alongside research facilities. Holidays are observed, and with it, traditional foods such as turkey and cobbler are eaten—with lemonade to wash it down.

One thing that makes the space station so distinctive is the experience that it gives the crews visiting the orbiting complex. After months of settling into a “routine” aboard the station, crewmembers never forget how special it is to be where they are.

“Of course, this 'routine' happens in the novel environment of space,” Expedition 5 Flight Engineer Peggy Whitson wrote in her thirteenth letter home from the station. “Being here, living here, is something that I will probably spend the rest of my life striving to find just the right words to try and encompass and convey just a fraction of what makes our endeavors in space so special and essential.”